Center-of-mass lift mechanism

Abstract

A lift mechanism includes a balance structure configured to hold an object, wherein the balance structure is rotateably connected to an arm structure at a pivot point. The pivot point is configured, and the object is positioned, such that the pivot point is substantially coincident with the center-of-mass of the object being moved. Weights may be selectively attached to the balance structure to adjust the center-of-mass. In one embodiment, the lift mechanism includes a base and an arm configured to rotate with respect to the base, wherein the arm is attached to the balance structure at the pivot point. In this way, heavy objects may be lifted, translated, and rotated into place safely in an efficient manner.

1. A lift mechanism of the type used to move an object relative to a reference surface, wherein the object has a center-of-mass, the lift mechanism comprising:
 an arm structure rotateably attached to a base, said arm structure configured to laterally move with respect to the reference surface, wherein the arm structure comprises a first portion extending from a second portion at a substantially oblique angle, the second portion rotateably attached to the base; 
 a balance structure configured to hold the object, wherein the balance structure is rotateably connected to the arm structure at a single pivot point on said balance structure, and said pivot point is substantially coincident with the center-of-mass of the object wherein said balance structure comprises one or more selectively removable weights, wherein adding or subtracting one or more weights to the balance structure aligns the center-of-mass of the object together with the balance structure to be substantially coincident with said pivot point; and 
 wherein said balance structure is rotatable with respect to said arm structure to orient said object from a first angle of orientation to a second angle of orientation with respect to said reference surface wherein said rotation of the balance structure with respect to the arm structure occurs around an axis passing through said center-of-mass and wherein said arm structure and said balance structure are disposed within said base such that said balance structure is rotatable with respect to said arm such that said center-of-mass does not extend outside said base. 
 
   
   
     2. The lift mechanism of  claim 1  wherein said base includes one or more rolling components configured to allow said base to move laterally with respect to the reference surface. 
   
   
     3. The lift mechanism of  claim 2 , further including a steering mechanism coupled to said base. 
   
   
     4. The lift mechanism of  claim 1 , further including a hydraulic actuator configured to rotate said arm structure with respect to said base. 
   
   
     5. The lift mechanism of  claim 1 , wherein said balance structure includes an access opening. 
   
   
     6. The lift mechanism of  claim 1 , wherein said balance structure may be clamped in place with respect to said arm to hold said second angle of orientation. 
   
   
     7. A lift mechanism of the type used to move an object relative to a horizontally disposed reference surface, wherein the object has a center-of-mass, the lift mechanism comprising:
 a base; 
 one or more rolling components attached to said base to allow said base to move laterally with respect to said reference surface; 
 an arm structure rotateably attached to said base, wherein the arm structure comprises a first portion extending from a second portion at a substantially oblique angle, the second portion rotateably attached to the base; 
 a balance structure configured to hold the object, wherein the balance structure is rotateably connected to the arm structure at a single pivot point on said balance structure, and wherein said balance structure comprises one or more selectively removable weights, wherein adding or subtracting one or more weights to the balance structure aligns the center-of-mass of the object together with the balance structure to be substantially coincident with said pivot point; and 
 wherein said balance structure is rotatable with respect to said arm to orient said object from a first angle of orientation to a second angle of orientation with respect to said horizontal reference surface wherein said rotation of the balance structure with respect to the arm occurs around an axis passing through said center-of-mass and wherein said arm structure and said balance structure are disposed within said base such that said balance structure is rotatable with respect to said arm such that said center-of-mass does not extend outside said base. 
 
   
   
     8. The lift mechanism of  claim 7 , wherein said base is generally “U”-shaped and wherein said rolling components includes three rolling components. 
   
   
     9. The lift mechanism of  claim 7 , further including a steering mechanism coupled to said base. 
   
   
     10. The lift mechanism of  claim 7 , further including a hydraulic actuator configured to rotate said arm structure with respect to said base. 
   
   
     11. The lift mechanism of  claim 7 , wherein said balance structure includes one or more access openings. 
   
   
     12. The lift mechanism of  claim 7 , wherein the balance structure may be rotated +/−360 degrees without the center-of-mass of the object extending outside said base. 
   
   
     13. The lift mechanism of  claim 7 , wherein said balance structure may be clamped in place with respect to said arm to hold said second angle of orientation. 
   
   
     14. A lift mechanism of the type used to move an object relative to a reference surface, wherein the object has a center-of-mass, the lift mechanism comprising:
 an arm structure rotateably attached to a base, said arm structure configured to laterally move with respect to the reference surface, wherein the arm structure comprises a first portion extending from a second portion at a substantially oblique angle, the second portion rotateably attached to the base; 
 a balance structure configured to hold the object, wherein the balance structure is rotateably connected to the arm structure at a single pivot point on said balance structure, and said pivot point is substantially coincident with the center-of-mass of the object wherein said balance structure comprises one or more selectively removable weights, wherein adding or subtracting one or more weights to the balance structure aligns the center-of-mass of the object together with the balance structure to be substantially coincident with said pivot point; and 
 wherein said balance structure is rotatable with respect to said arm structure to orient said object from a first angle of orientation to a second angle of orientation with respect to said reference surface wherein said rotation of the balance structure with respect to the arm structure occurs around an axis passing through said center-of-mass wherein said balance structure may be clamped in place with respect to said arm to hold said second angle of orientation and wherein said arm structure and said balance structure are disposed within said base such that said balance structure is rotatable with respect to said arm such that said center-of-mass does not extend outside said base. 
 
   
   
     15. The lift mechanism of  claim 14  wherein said base includes one or more rolling components configured to allow said base to move laterally with respect to the reference surface. 
   
   
     16. The lift mechanism of  claim 15 , further including a steering mechanism coupled to said base. 
   
   
     17. The lift mechanism of  claim 14 , wherein the balance structure may be rotated +/−360 degrees without the center-of-mass of the object extending outside said base.